Operational amplifiers are key building block circuits for a very wide variety of applications. Prior art Si-CMOS based operational amplifiers have a relatively low bandwidth, and less than 1 milliWatt of power handling capability. Example commercially available Si-CMOS operational amplifiers include Texas Instrument's part no. THS4304, which has a 3 GHz bandwidth, and Linear Technologies' part no. LTC6420-20, which is a differential amplifier.
Prior art InP-HBT based operational amplifiers have excellent linearity and bandwidths, but have poor noise figures and dynamic ranges. An example InP-HBT based operational amplifier is described by Z. Griffith et al. in “mm-Wave Operational amplifiers employing simple-Miller compensation, with OIP3/Pdc ratios of 211 (10 dB NF) and 144 (6.0 dB NF) at 2 GHz”, 2012 CSIC Symposium, pp. 1-4, 2008.
Prior art circuits for operational amplifiers include those that are described in U.S. Pat. No. 7,898,333, issued Mar. 2, 2011 to Griffith et al., U.S. Pat. No. 8,222,958, issued Jul. 17, 2012 to Griffith et al., and U.S. Pat. No. 8,354,885, issued Jan. 15, 2013 to Griffith et al., which are incorporated by reference as though set forth in full.
What is needed is an improved operational amplifier with ultra-high linearity, high gain, wide bandwidth, low noise figure, and high power-handling capability. The embodiments of the present disclosure address these and other needs.